Conventionally, with the development of wireless communication technologies, a base station (home base station) that is intended to be used in a specific area has been proposed in addition to a base station (macro base station) used for general mobile phones. The home base station has a smaller radio coverage than the macro base station. However, because the home base station is intended to be installed mainly in homes or small offices, mobile stations that are allowed to communicate with the home base station can access the home base station. Therefore, in general, to use the home base station, a user of a mobile station registers the mobile station in advance so that the home base station can perform wireless communication with the mobile station.
Patent Literature 1: Japanese National Publication of International Patent Application No. 2009-530987
Patent Literature 2: Japanese National Publication of International Patent Application No. 2007-507187
Patent Literature 3: Japanese Laid-open Patent Publication No. 2012-023598
Patent Literature 4: Japanese Laid-open Patent Publication No. 2010-171885
However, the above conventional technology has a problem as described below. FIG. 23 is a diagram illustrating a situation where a mobile station located in an area of a macro base station is interfered with by a home base station. As illustrated in FIG. 23, when a mobile station 100 is located in an area A17 of a macro base station B1, the mobile station 100 may be interfered with by a home base station B2 located in an area A18. Specifically, when the mobile station 100 does not have the right to access the home base station B2, the mobile station 100 is not enabled to communicate with the home base station B2 even though the mobile station 100 is located near the home base station B2. In this state, if the mobile station 100 communicates with the macro base station B1, because the power received from the macro base station B1 is weaker than the power received from the home base station B2, the mobile station 100 has to receive weak signals with greater interference, resulting in reduced reception quality.
To reduce the degradation of the reception quality, a method for limiting power or resource allocation in the home base station has been proposed. However, with this method, while the interference of mobile stations of the macro base station by the home base station can be reduced, the throughput of the home base station may be lowered at the same time.